Fat, oil and grease limits in wastewater

Failure to meet these limits can result in costly fines, however there several wastewater treatment methods available: 

What are FOGs?  

Fats, oils, and grease (FOGs) are organic substances, primarily fatty acids and soap. 

A number of industrial processes produce FOGs, including food processing and manufacturing industries. During production processed, FOGs are released and end up as a waste product or in tank or floor washings. 

Fats, oils, and grease must then be disposed of in a manner that meets regulatory standards. If the concentration falls below a consent level they can be discharged from site or may need to be treated first. 

FOGs are also produced by the food service industry and domestic households. 

Problems posed by fat, oil and grease in wastewater 

The presence of fat, oil, and grease (FOG) in industrial wastewater can lead to significant challenges in sewer systems and wastewater treatment plants. 

If released into the water system, they can cause blockages in sewers, risking flooding and pollution in streams and rivers. 

It is therefore crucial that fat, oil and grease limits are imposed to protect the environment and sewer infrastructure.  

Fat, oil and grease limits in the UK  

In the UK there are legal requirements in place to prevent fat, oil and grease entering drains and sewers.  

For example, under section 111 of the Water Industry Act 1991,  it is a criminal offence  discharge into the public sewers any matter which may interfere with the free flow of wastewater. 

Failure to comply with these requirements to these can lead to enforcement and prosecution. 

Furthermore, water companies may take legal action to recover any costs incurred while addressing flooding or pollution incidents.  

It is therefore crucial your wastewater adheres to fat, oil and grease limits to ensure your business is equipped to meet compliance demands and avoid costly fines. 

How FOGs are treated 

There are a number of wastewater treatment methods that can remove or limit fat, oil and grease, such as: 

Grease traps/grease interceptors: specially designed units which are placed in drain pipes to separate the fat, oil and grease from the rest of the wastewater. 

Enzyme dosing systems:  often used alongside grease traps, bacteria-forming enzymes are added to break down the FOGs, which are then biodegraded. 

Chemical treatment: coagulants and flocculants are added to the wastewater to promote separation, making them easier to remove 

Gravity separation: this treatment method separates fats, oils and grease from wastewater by utilising their natural density differences.  

Dissolved air flotation (DAF): air bubbles are introduced into the wastewater, which attach to the fat, oil and grease droplets and cause them to float to the surface.    

Find the right treatment plant for your business 

If your industrial processes result in fats, oils, and grease being present in your wastewater, Aqua Advice can help your business stay ahead of these challenges.   

We will work with you to identify the optimum treatment facility for your business.  

Get in touch today.